Pinterest has rolled out its first significant makeover since gaining popular attention in a move that sees it streamline the look of profile pages on the service.

The redesign had been anticipated for some time, with a number of media outlets including CNN speculating over possible changes — and the site has now rolled a more streamlined look. Elements previously position on the side of the page have been moved to the top to give photos and content greater prominence.

With Facebook continuing its rollout of Timeline and Twitter having revamped its service — albeit to mixed reviews — Pinterest is doing its own rearranging to help users connect with each other and content more freely.

Indeed, the new layout bears more than just a passing resemblance to Facebook’s new profile pages, as you can see from a screenshot of The Next Web’s Pinterest page.

The changes come right after Pinterest hit a notable milestone indicating that it is becoming more mainstream, despite being invite-only. A 21 percent growth in traffic in February saw it rank among the top 30 websites in the US for the first time, according to Hitwise Experian.

The site’s popularity has surged over the last year, with statistics showing that its traffic grew by more than 6,000 percent over the final six months of 2011, turning it into a service to rival Facebook, Twitter and other established social networks.

There are numerous examples which show that Pinterest is becoming a key driver of traffic across the Web. We’ve seen and heard reports that Pinterest gives more traffic than Twitter and serves more referrals than Google+, YouTube and LinkedIn combined, yet it is not rivaling the competition in the traditional sense as other services are benefiting from it directly.

A report this week suggested that Facebook, Google and YouTube — which are very much part of the Internet’s establishment — are the ones that are gaining the most from the service, despite it being a threat to their respective services.

Pinterest’s incredible growth led comScore to declare it the fastest standalone site to reach 10 million monthly users in the US. However, impressive though it is that Pinterest hit the landmark in just nine months, those with longer memories will recall that Formspring reached the figure at an even faster rate…only to fade away.

To capitalise on its popularity and continue to grow, Pinterest is said to be close to launching mobile apps. With the first step of its redesign now out of the bag, it seems that we can expect further developments very soon.